Frigid unit



0a. 27, 1936. w c. A. STICKNEY' FRIGID UNIT I Original Filed Nov. 4, 1927 2 Shets-Sheet 1 filial!!! INVENTOR.

Charles A. Sficxn signal ATTORNEY;

Oct. 27, 1936. c. A. S-I'ICKNEY FRIGID UNIT Original Filed Nov. 4, 1927 2 Sheets-Sheet 2 INVENTOR. NO

m .A P u m n S A L M A 6 I. M F r 8 Charles. A. Sh'cIr ATTORNEY.

. Reissued Oct. 27, 1936 I mom can I 01ml s. Stickney, maul, late of Rockford,

11] Ill. N. J.

., by John F. MoCanna, usignee, Rockford, a saignor to Elmer H. Schm Englewood,

Original No. 1,791,850, dated February 10, 1931.

Serial No. 230,958, November 4, 1927. Application for reissue October 10, 1932, Serial No.

24 Claims. (Cl. 62-115) This invention relates to refrigerating appa ratus'generally but has special reference to a frigid unit designed for handy installation in'the ice compartment of ordinary ice boxes in converting the same from ice to mechanical refrigeration, although, of course, the invention is not limited to application in that way but may be built in by the maker or seller of the refrigerators. The invention embodies various features which, for purposes of convenience, may be enumerated briefly as follows:

l. The provision of a unit having condensing and expansion chambers provided in hot and cold sections of a two-chamber casing, thus making for extreme compactness and, at the same time,

permitting handy installation in the top of a refrigerator cabinet, the ribbed walls of the ,hot section when the unit is so installed being exposed outside the refrigerator above the same for ideal heat dissipation and the ribbed walls of the cold section being exposed within the refrigerator for heat absorption.

2. The provision in connection with the twochamber casing, of a compressor built in as a part of a unitary assembly along with the housing of the electric motor furnishing the power for the operation thereof, the over-all dimensions of the unit being reduced practically to a minimum as a result of such novel design and construction.

3. The provision of a compressor of veryvsimpie and durable construction as well as miniature proportions, especially well adapted to assembly in the manner contemplated, and one wherein the pistons are thrown outwardly by centrifugal action and forced inwardly by an eccentric antifriction bearing ring, so that no complicated operating connections are required and the device is smooth and noiseless in operatiorr.

4. The provision in a frigid unit, of. means for periodically defrosting the cold section by placing the condensing and expansion chambers in unrestricted communication. A special feature of the invention is to provide a reducing valve arranged to be operated at-intervals as the condensed refrigerant collects in the condensing chamber and to provide in connection with this valve means suitably operated by the motor driving the compressor for periodically opening the reducing valve wideopen for the defrosting operation.

Thus, the unit may be defrosted in a few minutes,

every two or three hours or more without the serious interruption to refrigeration which would otherwise be necessitated.

5. The provision of a unit of the present character where the motor housing and compressor casing are hermetically sealed with the twochamber casing, thus eliminating stumng boxes, etc.

The invention embraces the above and other features as hereinafter described. Referring to the accompanying drawings a Figure 1 is a central, longitudinal section through the frigid unit of my invention, indicating how the same is arranged to be installed in the wall of a refrigerator cabinet:

Figs. 2 and 3 are horizontal sections taken on the lines 2! and 3-3 of Fig. l;

Fig. 4 is an enlarged detail in elevation'of a part of the train of reduction driving connections for the cam which periodically operates the defrosting valve, the other partof the connections and the cam itself appearing in the upper part of Fig. l; and

Fig. 5 is a section through the-combination exhausting and filling valve, taken on line 5-6 of Fig. 1.

The same reference numerals are applied to corresponding parts throughout the views.

The frigid-unit has the main body portion thereof formed by a two-chamber casing I in the form of a unitary casing providing a condensing chamber 6 and an expansion chamber I sepacerned the same advantages might be gained by casting the two chambersseparately and joining them togeth The condensing chamber i being the heat r ting section maybe referred to as the hot section and has ribs 9 on the walls thereof for radiation of the heat therefrom. The expansion chamber I being the heat absorbing section. may be referred to as thecold section and has rlbs ill on the walls thereof for heat absorption. Manifestly, the one section being hot and the other section cold it becomes important to avoid conduction from one to the other and for this purpose it is preferred to provide insulating material ll, such asfeltor the like,heldinplacebya plate I! suitably having a press fit inside the cold section. An electric motor It has the housing It thereof closing the top of the hot section andsupports the housing I! of the compressor it within the hot section, thus cutting down the over-all dimensions of the unit and making for the best compactness. By reason of its proportions the unit may be mounted in a refrigerator cabinet in the manner indicated in Fig. 1 where the flange ll, cast integral with the casing I in the vicinity ofthepartitionwalllthereimisshownresting' onagasket II on the top wall II or arefrigerator cabinet, the cold section protruding into the cabinet'through an opening 20 in the top wall in the manner shown. It is contemplated that the I ,weight of the unit alone will be sufllcient to hold it in place. However, screws or bolts may be provided passing through the flange n into the top wall of the cabinet if that is desired. The ring 2| I at the top of the unit will serve in the setting or removal thereof When the unit is installed as Just described it will be evident that. the ribs I of the hot section, and the ribs 22 of the motor housing as well, are ideally situated for heat radiation since the heat rises natm'ally therefrom. In a similar manner the ribs III of the cold section are ideally situated for heat absorption, inasmuch as the heat rises naturally thereto. In operation, it

may be stated at this point that the compressor It supplies compressed gweous refrigerant, such as sulphur dioxide, to the condensing chamber 5 where the refrigerant is condensed from the compressed gaseous state to liquid form, the heat being dissipated to the atmosphere by radiation from the ribs 9. The liquid refrigerant is then called to the storage compartments formed in a closure 25 provided for the lower end of the easing to close the cold section. The compartments 24 serve the usual purpose of freezers as for example in making ice cubes and the like.

F'I'he reducing valve 2! is reciprocable in a plug 26 mounted in the partition wall I in the manner shown and is normally held to its seat 21 by a coiled compression spring 28. An adjustable tap its pet nut 29 threading on the upper end of the stem of the valve 23 is arranged to be set accurately-at the factory when the unit is bled and should seldom, if ever, require any resetting. A float III has the arm thereof pivoted at II on a bracket 32 suitably formed integral with the upper end of the plug 2! and has a link connec- I tion at 33 with a rocker arm 34 pivoted at II on the bracket 32 The end of the arm 34 engages the under side of the tappet nut 29 and is arranged to lift the valve 23 off its seat against the action of the spring 28 when the float 30 is caused to rise as a result of a collection of condensed refrigerant in the bottom of the condensing chamber. The refrigerant flows into the plug through openings 30 and flows past the end of the valve where the same is fluted, as indicated at 31.

'Manifestly, the opening of the reducing valve will be very. slight for a given movement of the float, the operating connection between the float and the valve afforded by the linkage having a ratio of about 25 to 1. In other words, such a restriction is maintained by the valve 23 that refrigeration will result upon the passage of the liquefied refrigerant from the high pressure area of the condensing chamber to the low pressure area of the expansion chamber. It will also be evident that there will be little danger of clogging of the reducing valve inasmuch as the collection of any dirt or grit in the plug 26 at or around the seat 21 tending to prevent'the pasage of the liquid refrigerant past the valve will merely result in the collection of more andmore liquefied refrigerant in the condensing chamber and consequently will cause a greater and greater opening of the reducing valve until eventually the dirt or grit will be washed through. The reducing valve should, therefore, never require attention inasmuch asits diihculties are automatically remedied.

It is well known how the frost coils of the standard type refrigerators become so, heavily frosted that the emciency is somewhat impaired, and the coating has to be removed with a pick or else the refrigerator has to be turned off long enough to allow the coating to melt off, According to the invention the valve 23, in addition to serving as a reducing valve, is made to function as a defrosting valve for placing the condensing and expansion chamber in unrestricted communication. A push rod 38 slidably received in a hole 38 provided in the housing I! is arranged, as hereinafter described, to depress the end of the rocker arm 34 to open the valve 23 wide open So that both temperature and pressure may be equalized in the two chambers just long enough for the frost coating on the walls of the expansion chamber to melt on, the water dripping therefrom being drained from the refrigerator in the usual way, As hereinafter described, it is contemplated the provision of means operating the valve to defrost the unit periodicallyduring the normal operation thereof, the unit being defrosted, for example; every two or three hours or more and in that way being made to operate always at its highest emciency. This method of defrosting as contrasted with the old method where the unit was thrown out of operation, will not consume enough time to seriously interrupt the refrigeration.

The compressor It, as stated above, has the casing I thereof suspended from the housing ll of the motor I! within the hot section of the frigid unit. The connection therebetween is air tight in order that the pressure in the condensing chamber 8 may be maintained and in order further that the pint or so of oil stored in the bottom of the casing I! for the lubrication of the compressor l8 and other parts operating therein will not leak therefrom. A wall 40 fastened to a flange inside the housing ll serves as a baille to retain the oil in the casing l5, even though, the unit in shipment happens to be laid on its side. The wall 40 is also conformed to provide an annular trough 42 into which the oil will flow in the event the unit happens to be stood upside down. The armature 48 of the motor I! is, therefore, protected under all circumstances against contamination from oil despite the fact that the shaft ll thereof passes The compressor l6 comprises a rotary cylinder block 48 fixed to the lower end of the shaft 44 as by'means of a pin 49 passed through the hub portion 48 of said block. The latter is mounted for rotation on a post 50 fixed in a center hole il'in the bottom wall of the casing I! as by means of a nut 52. The post 50 has a low pressure intake port 53 and a high pressure exhaustport M. The former communicates through a central passage 55 in the plug 50 with the upper relatively freely through a center hole 45 in'the end of a pipe 6| extending downwardly through the partition wall I into the expansion chamber 1. The port I, on the other hand, communicates through a passage ll with the condensing chamber 8. The supply of gaseous refrigerant for the compressor it will now be clear is supplied through the pipe 66 from the expansion chamher I and the liquefied refrigerant produced in the condensing chamber its the result of the condensation of the compressed gas supplied to said chamber through the passage 51. The cylinder block ll has a plurality of radial cylindrical bores 58 provided therein, only two being shown as a matter of convenience although it is preferred to employ as many as five. The bores 68 have solid pistons 59 received therein with a fairly close fit and arranged to be reciprocated from the intake position shown at the left in Fig. 1 to. the exhaust position shown at the right in said figure. On the intake stroke of the pistons the bores 58 are .in communication through approximately 45 of their travel by reason of the provisions of aiateral extension 53' of the intakeportion 53, as seen in Fig. 2. Similarly the home are placed in communication with the exhaust port 54 through approximately 45 of their travel when the pistons approach the inner end of their compression strokes by reason of the fact that the exhaust port 54 has a lateral extension 54, as seen in Fig. 2.

pistons have suflicient mass and the speed of rotation is high enough to insure the throwing out of the pistons on the intake stroke under centrifugal force. The pistons "have rounded outer ends as shown bearing against the inner periphery of a ring Gil disposed eccentric with the post I and cylinder block 48. The ring 60 forms the inner race for an anti-friction bearing having balls 6| disposed between said ring and an outer race ring 62, seated, as indicated at 63, in a recess provided therefor in the bottom of the casing it. Thus. in the rotation of the cylinder block II the pistons 59 are thrown out against the ring 60 under centrifugal force and are moved inwardly on their compression strokes by reason of the eccentric position of the ring. Since the latter forms a part of an anti-friction hearing it will be evident that the operation is smooth and quiet and does not consume very much power. Lubrication of the pistons and cylinder bores of the compressor, as well as the antifrictlon bearing referred to is obviously taken care of adequately since these parts operate in an oil bath, as previously indicated. In passing. attention may be called to the fact that the passage Ii extends entirely through the'post 60 for communication with the inside of the hub ll of the cylinder block 48 and that the hub has a hole 84 drilled longitudinally therethrough. Thus.

the inside of the compressor casing ii is always in communication with the expansion chamber.

This insures the cooling of! of the compressor- 1 The fact that the center hole I! in the wall ll is large enough'for free therethrough of the shaft 44 also results in the inside of the -The valve 23, as stated before, is arranged to beop'eratedperiodically for the defrosting of the cold sectionby depresion of the push rod I! during the operation of the compres or. A worm -85 isfixedonorprovidedasanintegralpartofthe hub ll of the cylinder block so as to be operated by the motor I! whenever the compressor "is operated, it being,'o'f course, understood that the operation of thei'rigid, unit by the elec- .tric motor will be thermostatically controlled to maintain a predetermined desired temperature in the ref igerator cabinet. In other words, the motor l3 will operate only intermittently as determined by the rising and falling of the temperature in said cabinet. The worm 6i meshes with a spur gear 68 fixed on a shaft 61 received in bearings suitably provided on a wall 68 cast integral with the wall 0. The shaft 61 has a screw 69 threaded in the end thereof eccentric to its axis to serve as a crank pin for a pawl I operating on a ratchet wheel I i, the pawl being held in engagementwith the ratchet suitably by means of on the ratchet wheel Ii for operating a second pawl It on a ratchet wheel 15, spring means being provided at 16 to keep the pawl in proper engagement with the ratchet. The latter is arranged to turn a shaft 16 and with it a cam 'll progressively in one direction whenever the motor is operated. The. thought is to cause the cam ll to turn through one complete revolution once in about every two or three hours of operation of the frigid unit, the profile of the cam being such that the valve 23 will be held open for defrosting purposes for a period of a few minutes. The cam is arranged to operate against one end of a rocker arm ll pivoted at 19 and having the other end thereof arranged to bear down upon the end of w sity for auxiliary spring means to bring about the return movement of the push rod.

' In closing, attention may be called to the combination exhausting and filling valve 80 appearing in Figs. 1 and 5. The latter ,comprises a T-shaped plug threading intoan opening 8i provided in the motor housing ll and'communicating with the inside of the condensing chamber 6. The plug has oppositely directed nipple portions "and I3, communicating with the central bore 84 thereof, the one nipple portion being arranged to have connection with an exhausting pump whereby all of the air may be pumped out of the unit, after which the other nipple portion having connection with a' reservoir containing SO: will serve to let in the gas to replace-the air. The bore 84 is then sealed by the tight. closing of the needle valve 05 by ensagement'of a key with the square end ii of said valve and a cap 81 is then threaded on the upper end of the plug to conceai the valve and thus avoid any likelihood of the with when the unit is in.

same being tampered service.

While the description of the invention has been applied to one specific embodiment it will be apparent that the same is capable of a considerable" range of variation from the particular details herein illustrated, It is, therefore, the intention in the appended claims to cover all legitimate modifications and adaptations-of'the present invention which will, no doubt, suggest themselves to one skilled in the art as a result of the present It is claimed:

1. A device of the character described comprising in a single unit a hot section in the form of a finned cylinder of a certain diameter providing a condensing chamber therein, and a cold section in the form of anotherflnned cylinder contiguous and coaxial with the other cylinder and of a smaller diameter providing an expansion chamber therein; there being; an annular shoulder formed at the junction of the two cylinders for supporting said unit on a refrigerator cabinet whereby the hot section is exposed outside the cabinet and the cold section is exposed inside the same, and there being means providing restricted communication between the sections toproduce refrigeration in the cold section in the usual way,- means for continuously supplying compressed refrigerating medium to the hot section and exhausting expanded refrigerating medium from the cold. section, and means whereby the two chambers may be automatically placed in comparativcly unrestricted communication whereby to defrost the walls of the expansion chamber.

2. In a device of the character described comprising means providing a condensing chamber, means providing an expansion chamber, and a compressor exhausting into the condensing chamber and having the inlet side thereof communicating with the expansion chamber, a reducing valve aflording restricted communication between the two chambers to cause refrigeration in the expansion chamber, and means arranged to be automatically operated to place the two chambers in unrestricted communication whereby to defrost the walls of the expansion chamber.

3. A device as set forth in claim 2 wherein the last mentioned means is arranged to be operated at predetermined intervals.

4. A device as set forthin clalm '2"wherein the last means automatically operates said reducing valve to wide open position at predetermined intervals.

5. A device as set forth in claim 2 including means for operating said compressor having a reduction drive connection with 'the'last mentioned means for periodically operating the same at prescribed intervals.

6. In a device of the character described comprising means providing a condensing chamber, means providing an expansion chamber,- and means for supplying compressed gaseous refrigerant to the condensing chamber and exhausting expanded refrigerant from the expansion chamber, a reducing valve for affording restricted communication between the two chambers to cause refrigeration in the expansion chamber, afloat mechanism in the condensing chamber opera-- tively associated with said valve to open the latter when a certain amount of condensed refrigerant collects in said chamber, and supplemental means arranged to operate said valve by operation of its float mechanism to place the two chambers in unrestricted communication for the purpose contemplated.

'1. A device of the character described comprising a casing providing in a single unit a condensing chamber forming a hot section and an expansion chamber forming a cold section, means for mounting. said unit in the wall of a refrigerator cabinet so that the condensing chamber is disposed outside the cabinet and the "expansion chamber is disposed inside the same, there being a reducing valve afl'ording restricted communi-' cation between the two chambers. a compressor having the intake side thereof communicating withtheexpansionchamberandtheexhawt side communicating with the condensing chamber, means for operating said compressor comprising an electric motor having the housing thereof supported on the outer end of said casing and having the casing of the compressor supported thereby within the condensingchamber, the rotor shaft of said motor having a direct driving connection with said compressor. andthe compressor casing being arranged to contain a supply of lubricating oil, a bailie wallbetween the motor housing and the compressor casing having the rotor sum passing freely through an opening therein, said wall being conformed to provide a pocket for the lubricating oil whereby to exclude the oil from of the frigid unit, there being a partition wall between said chambers, said casing having means for supporting the same on the wall of a refrigerator cabinet so that the condensing chamber is exposed outside the cabinet and the expansion chamber projects into the cabinet, an electric motor housing mounted on top of said casing serving to close the condensing chamber, a compressor casing suspended from the motor housing within the condensing chamber, a rotary compressor within said casing, the stator of saidcompressor comprising a postfixed with respect to the compressor casing and providing a bearing for the rotor of said compressor, an electric motor armature in the electric motor housing disposed vertically and coaxial with saidpost, saidarmature having a bearing at its upper end in its motor housing and having at its lower end a direct driving connection with the rotor of said compressor whereby the post serves as a bearing for the lower end of said armature, there being an intake passage for said compressor communieating with the expansion chamber'and an exhaust. passage for saidcompressor communicating with the condensing chamber.

10. A structure as set forth in claim 9 wherein the compressor casing and motor housing are hermetically sealed together, and wherein said post has a passageway provided therein establishing communication from the intake passage for the compressor between the expansion chamber and the housingof said motor substantially as and for the purposes described.

ii. A structure as set forth in claim 9 includ ing a rod extending through the wall of said compressor casing into the condensing chamber and arranged when moved to operate the reducing valve to wide open position, a gear turning with the motor armature in the operation of the latter, a tappet for communicating endwise movement to said rod and means including reduction gearing driven from said gear arranged periodically in the operation of said armature to operate said tappet.

12. A structure as set forth in claim 9 including a baflie wall separating the compressor casing fromthe motor housing, there being a supply of lubricating oil in the compressor casing, and said bailie wall having an annular trough provided therein arranged to have the lubricating oil enter 7s reducing valve is permanently set for a normal restriction but is movable, while remaining so set frmn the position of normal restriction to one of less restriction, said reducing valve being arranged to be operated automatically to the latter position by the last mentioned means set forth inclaim2forthepurposespecified.-

14. Refrigerating apparatus having a condens pressor supplied with gaseous refrigerant from the expansion chamber and arranged to deliver compressed refrigerant to the condensing chamber for subsequent delivery through a'restricted orifice to the expansion chamber, a motor for driving the compressor, and means for periodically subjecting the walls of the expansion chamber to heating whereby to defrost the same, said means having a reduction drive connection with the motor whereby tov be rendered operative at predetermined intervals.

16. In a refrigerator comprising means providing a condensing chamber, means providing an expansion chamber, and a compressor exhausting into the condensing chamber and having the inlet thereof communicating with the expansion chamber, a reducing valve normally affording restricted communication between the two chambers whereby to cause refrigeration in the expansion'chamber, said reducing valve being constructed for movement from a position of normal restriction to a position establishing open communication between said chambers, whereby to permit defrosting of the walls of the expansion chamber, and .means for automatically moving saldvalve from one position to the other.

17. In the art of producing refrigeration by means of a refrigerating system including an evaporator normally maintained at a frost producing temperature,- that step which comprises periodically at intervals utilising heat generated within the system to raise the temperature of the walls of the evaporator to a frost melting temperature.

ing gaseous refrigerant therefrom and for returning liquefied refrigerant to the vaporator which comprises operating the syste to maintain the average temperature of the evaporator below 32 F. and also at frequent intervals during each twenty-four hour period to temporarily raise the temperature of the evaporator above 32 F. for a periodsuflicient to cause a melting of any frost accumulated on said evaporator.

21. The method of producing refrigeration through the agency of a refrigerating system including an evaporator and means for withdrawing gaseous refrigerant from and for returning liquefied refrigerant to the evaporator which comprises operating the system. to maintain the temperature of the evaporator normally below 32 F. and also at intervals of less than twentyfour hours to temporarily raise the evaporator temperature above 32F. for a period sufficient to cause a melting of any frost accumulated on said evaporator.

22. The method of producing refrigeration through the agency of a refrigerating system including an evaporator and means for withdrawing gaseous refrigerant from and for returning liquefied refrigerant to the evaporator which comprises operating the system to produce an evaporator temperature normally below 32 F.

20. The method of producing refrigeration through the agency of a refrigerating system including an evaporator and means for withdrawand at frequent intervals during each twentye four hour period to temporarily raise the evapocluding an evaporatorand means for withdrawing gaseous refrigerant from and for returning liquefied refrigerant to the evaporator which comprises operating the system to maintain the temperature of the evaporator normally below 32 F. and, at intervals of less than twenty-four hours, to temporarily raise the evaporator temperature above 32 F. by utilizing heat from within the system to cause a melting of any frost accumulated on the evaporator.

24. The method of producing refrigeration through the agency of a refrigerating system including an evaporator and means for withdrawing gaseous refrigerant from and for returning liquefied refrigerant to the evaporator which comprises operating the system" to maintain the temperature of the evaporator normally below 32 1''. and, at frequent intervalsduring each twenty-four hour period, to temporarily raise the evaporator temperature above 32 F. by utilizing heat from within the system to cause a melting of frost accumulated on the evaporator.

. JOHN 1 moms, 'Assimiee of Charles A. Sticlmev. Deceased. 

